While the two have previously released Android-powered devices, notably the Nokia X, the non-Windows Phone version of its flagship Lumia line would be a first for Nokia.

The new Lumia will supposedly be released under the Nokia by Microsoft brand, according to evleaks, which reported the rumor. The Twitter account, which has proved spot-on in past leaks, previously reported Microsoft would eventually rebrand all of Nokia's Windows Phone devices as "Nokia by Microsoft."

It's not clear whether the rumored handset would run a full version of Android or follow the same model as Nokia's X line, which are Android-powered but don't rely on Google services like the Play Store. Instead, the devices offer a selection popular Android apps through third-party app stores, along with the Nokia Store, similar to the approach Amazon took with its Android-powered Fire tablets.

The company recently added a new low-cost smartphone to the Nokia X lineup, the Nokia X2, slated to hit shelves later this month. Microsoft has used its Nokia X devices to lure feature phone owners in emerging markets.

Nokia was already one of Microsoft's closest partners for mobile when the Redmond-based company officially acquired Nokia's Devices and Services business in 2013 for $7.2 billion.